<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title></title>
    <script>
        var shenGao = parseFloat(prompt("请输入你的身高(cm)",155));
        var tiZhong = parseFloat(prompt("请输入你的体重(斤)",110));
        var BIM = (shenGao-108)*2 - tiZhong 
       if( BIM > 10){
           alert("你的体重偏瘦")
       }else if(BIM < -10){
            alert("你的体重超重")
       }else{
        alert("你是标准体重")
       }
    </script>
</head>
<body>
    
</body>
</html>